Fiths



(No Model.) 2 Sheets-Sheet 1 W. U. GRIFFITHS 81; H. NIEDER'MAYER. AIR GOMPRESSINGAPPARATUS.

No. 547,882. Patented Oct. 15, 1895.

W IINVIENT-ORS (No Model.) 7 .2 Sheets-Sheet 2. W. U. GRIFFITHS 82; H. NIE-DERMAYER.

' AIR GOMPRB SSING APPARATUS,

No. 547,882. Patented Oct. 15, 1.895.

' INVENTORS,

"(DREW EGIAHAM. FHOTOUTNQWASHINGI'DNJB.

' UNIT D STATES PATENT OFFICE.

WILLIAM U. GRIFFITHS AND HENRY NIEDERMAYER, OF PHILADELPHIA,

PENNSYLVANIA.

AIR-COMPRESSING APPARATUS.

SPECIFICATION forming part of Letters Patent No. 547,882, dated October 15, 1895.

i I Application filed August 17, 1895- Serlal No 559,639. (No model.)

To aZZ whom it may concern:

Be it known that we, WILLIAM U. GRIF- FITHS and HENRY NIEDERMAYER, of the city of Philadelphia and State of Pennsylvania, have invented certain new and useful Improvements in Air-Compressing Apparatus, whereof the following is a specification, reference being bad to the accompanying drawlugs.

In said drawings, Figure 1 represents a vertical longitudinal section through the apparatus. Fig. 2 is a top or plan View of the exterior thereof, and Fig. 3 a top or plan View of the interior with the cap or upper portion of the casing removed.

The object of our, invention is to provide an efficient means for obtaining automatically an unlimited number of successive charges of compressed air by means of a stream of water admitted under pressure to a closed receptacle.

In the drawings, A represents a metal tank, preferably of cylindrical form, having a cap or cover A, which extends upwardly to atford room for some of the working parts, but is of reduced transverse section to avoid increasing too greatly the idle air-space within the tank. In Fig. 2 the form of the upward extension of the cap or cover is indicated, one portion thereof 0. being substantially domeshaped and the other portion 0. extending radially outward from-the center of the domeshaped portion, into whose periphery its walls merge, as indicated. At the bottom of the tank A are an inlet-pipe B for water and a water-outlet pipe 0 of considerably greater diameter than said inlet-pipe. At the top of the cap is an outlet D for the compressed air,which outlet is preferably controlled by means of a checkvalve in the enlarged portion (1 of the outletpipe. The water-outlet pipe 0 is controlled by a valve E, attached to a stem F and adapted to move longitudinallyin a guide 0, mounted within the pipe. A float G, which is termed the main float, is mounted to slide vertically upon said stem F, its range of movement being limited down ward by contact of a boss 9 with the top of the valve E and upward by contact of a similar boss 9 with a shoulder f, formed by the enlarged upper portion H of the rod F. Said upper portion terminates in a curved finger h, which is adapted to form a seat for a float I, whose arrangement and relation to the other parts will presently be L, pivoted to said hanger at Z, and also pivotally connected at one end to the upper portion H of the rod F, as indicated at l, and at the other end to a counterbalance M. Near the top of the tank A a pipe N, communicating with the outer air, leads upward by a rightangle turn, as shown, to a point well up within the lateral extension 0. of the cap A. Said pipe serves alternately as a temporary discharge-pipe for compressed air and as an inlet-pipe for a succeeding charge, and will hence be termed the air inlet and outlet pipe for oonvenienceof description. Said pipe carries at its upper end a bracket 01 and bifurcated guide-piece 0. To the bracket is pivotally connected a transverse rod c, which carries the float I, said rod being guided between the bifurcations of the guide-piece 0. The inner end of the pipe N is controlled by a valve P, mounted upon the rod 2'. When the outlet-valveE is closed and the rod F consequently in its lowest position, the secondary float I hangs in the curved supportingfinger h (the rod 1' being retained between the bifur- I cations of the guide 0 to prevent lateral displacement) and the valve P is closed. The buoyancy of the main float G is not sufficient to raise the rod F against the internal pressure of the compressed air, which tends constant-ly to hold the valve E upon its seat. When, however, the said pressure has been relieved by the opening of the Valve P, which occurs when the water rises sufficiently to raise the float I, the main float G has sufficient buoyancy to rise and open the valve E. The counterbalance Mis suflicient to sustain in a raised position the rod F, valve E, secondary float I, and its connected parts so long as the main float G is sustained by the presence of the water within the tank; but when the weight of said main float is added to that of the other parts (by the fall of said float to v g v its lowest position, where it rests upon the valve E) the counterbalancewill be overcome and the parts will descend.

The operation of the device is as follows: Assuming that the valves E and P are both closed, water is admitted -under pressure through the water-inlet pipe B, and the air within the tank is compressed. The compressed air is led off through the outlet D and utilized for any desired purpose. With the rise of the water-level within the tank A the main float G rises until it reaches the limit of its movement upon the rod F and bears up- Ward against the shoulder f. Thereafter the further rise of the Water completely suhmerges said float, and when the water reaches the secondary float I and submerges it to the desired extent the buoyancy of the latter is suflicient to open the valve P against the inr ternal pressure, whereupon the residue of compressed air rushes out rapidly through the pipe N and a momentary sudden rise of water occurs. The pressure being relieved, the float G immediately rises, opening the valve E, and as the area of the dischargepipe 0 greatly exceeds the area of thewaterinlet pipe B the Water-level falls rapidly. The valve 1 is kept open during the period of the escape of the water by reason of the fact that the counterbalance M is sufficient to sustain the rod F, float I, and connected parts in their raised position during the period that the Water is falling. Consequently a fresh charge of air is admitted through the pipe N during the period of discharge of the water. When, however, the tank A has been substantially cleared of Water, the descent of the main float G will have caused it to bear upon the top of the valve E, and the additional weight causes the descent of the rod F and closes the valve E. Simultaneously with the closing of the valve E the valve P is also closed by the descent of the secondary float I. The compressing operation then occurs in the same manner as that just described, so that an indefinite number of charges of compressed air can be automatically obtained through the action of the parts set forth.

Having thus described our invention, we claim- The combination, with a tank having" a water-inlet pipe,a water-outlet pipe, an outlet valve, an outlet pipe for compressed air and an air-inletand-outlet, of a longitudinally movable rod, operatively connected with the Water'outlet valve; a main float havingalimited range of movement upon said rod; a counter-balance connected with said rod; a secondary float adapted to be supported by said rod; and an airinlet-and-outlet valve, operatively connected with said secondary float, substantially as set forth.

WM. U. GRIFFITHS. HENRY NIEDERMAYER.

Witnesses:

G. HERBERT J ENKINB, JAMES H. BELL. 

